op milwaukee



P 1932- R. G. MARQUARDT WIRE SPRING CUSHION AND METHOD OF'MAKING THESAME Filed July 24, 1950 abtowm Patented Sept. 6, 1932 n i UNIT-EDSTATES PATENT OFFICE COMPANY, or MILWAUKEE, wIsooNsrN, A- conronnmronorW sconsin WIRE SPRING CUSHION AND METHCD OF MAKING THE SAME Applicationfiled July 24,- 1930; Serial no. 470,323.

My invention relates to improvements in wire spring cushions and methodsof making the same, with particular reference to the spirally coiledsprings of chair bottoms, bed bottoms, etc., which require to beyieldingly linked together in a manner to hold them with their axessubstantially parallel.

Heretofore, the linkage employed for connecting the individual spiralshas given considerable trouble and has been a large factor in thedisorganization of chair bottoms and bed bottoms under conditions ofuse, the links tending to pull unequally upon the spiral coils andfrequently becoming disengaged or displaced. Attempts to overcome thesetroubles have given rise to so many problems that in the more modernspring cushions helically coiled linkages are employed which do notpermit a release of the individual spiral cushioning coils, but requirea dismounting-of the entire assembly, or a large portion thereof, inorder to permit the replacement of a single spiral coil.

The object of my invention is to provide sets of crossed helicalcouplings which may be independently disengaged at either end of anyhelix by reason of the capability of resilient flexion under manualpressure.

. A further object of my invention is to provide means to facilitate theapplication of manual pressure to displace a resilient locking arm atthe extremities of the helices to allow the release of a strand of aspiral coil which isotherwise securely locked to the helix.

In the drawing Figure l is a plan view of a fragment of a bed bottom orchair bottom to which my invention has been applied, one of the spiralcoils and two of the crossed helical couplings being illustrated infull.

Figure 2 is an enlarged plan view showing a fragment of the top strandof a spiral cushion coil from the under side as it appears duringflexion of the locking arm of the helix while the latter is being forcedinto strand engaging relation with the spiral coil.

Figure 3 is a view of the parts showing in Figure 2 after completion ofthe coupling.

Figure 4 is a View of one end portion of a helix seen at right in Figure2. i v

Like parts are identified by the same reference characters throughoutthe several views. I

The spiral cushion coils may be assumed to be of the hour glass form,being constricted medially and expanded at both ends. Ordinarilythesecoils will be assembled with their aXesext-ending Vertically and will belinked together by. crossedv and interlaced pairs of helical coils '10and 11, the extremities of which engage the top strand 12 of the spiralor cushion coil, as-clearly shown in Figure 1. The parts thus fardescribed may be assumed to be of ordinary construction except as to thefeatures hereinafter described in detail. At-the endsof each helixthestrand of Wire of which itis composed is looped in a plane substantiallyparallel'with the axis of the helix orv coincident therewith, therebyforming ahook shaped inember'15 forv env gagementiwith the top strand1201? one of the cushion: coils; "The extremity, of 'the strand isturned preferably in a plane sub:- stantially at right angles totheplane of the hook 15 and curved, as best shown in Figures 2'and 3, toform a retaining bow 16 in such proximity to thezend turn of the helixas to normally prevent a release of the strand 12 from the hook 15. I l

By bending the retaining bow or locking arm 16'away from the end turn 17of the helix, i. e., along a line generally parallel with the axis ofthe helix, the strand 12 may bepermitted to passinto the hook 15 or bereleased from engagement thereby.

The curved or bow form of the locking arm 16 facilitates use'of thestrand 12 in applying the necessary'pressure for a retraction of thislocking arm,'inasmuch as the strand 12 may be engaged between either endof the boW and the endturn 17 of the helix, whereupon relative pressureof. the strand and bow upon each other will cause the strand to" movewith a wedging action across the point where the bow is in greatestproximity to the end turn 17. p By making thehelicalcoil'from'highlyreangles to its position nnrmronn e. MARQUARTDT, or MILWAUKEE,wrsooiv'sm, nssrenon'ro MARQUARDT I silient steel wire, an accidentalrelease of the hook from the strand 12 will not be possible, since noaccidental movements of the parts upon each other will cause the strand12 to move along the curve of the bow with pres sure suflicient to causeits release, this being in part due to the fact that the locking armextends at right angles to the plane of the hook, and the strand 12 isnormally perpendicular to that plane at the point where is passesthrough the hook, and therefore in a plane substantially parallel tothat occupied by the locking arm.

In assembling my improved spring cushion, the spiral coils may all beassembled in place on the supporting bed or chair bottom and the crossedhelical coils interlaced in pairs. Thereupon, each hook may be engagedwith its associated strand 12 by engaging the strand between the curvedextremity of the locking arm 16 and the associated end turn 17 of thehelix andapplying manual pressure as above described, to cause thestrand 12 to pass into the hook, the looking arm 16 then movingresiliently to normal locking position. Each end of each helix may thusbe independently engaged with an associated strand 12 and a reversal ofthe operation will release the strand 12 of any given spiral coilwithout releasing any of the other coils.

I claim:

1. A bed bottom structure including a helical coupling coil of resilientmaterial having a single looped end portion extending in a planesubstantially parallel to the longitudinal axis of the coil andterminatingin a substantially bow-shaped laterally extending snap arm inloop closing relation to the end of the coil whereby to provide a snapaction between said arm and the adjacent terminal coil of the springwhen connecting a strand of wire to said loop.

2. A bed bottom structure including a helical coupling coil of resilientmaterial having a single looped end portion extendingin a planesubstantially parallel to the longitudinal axis of the coil andterminating in a laterally extending arm in loop closing relation to theend of the coil, said arm being bow-shaped and having its intermediateportion in closest proximity to the adjacent helix, whereby to retain astrand of wire in said loop against movement through the space betweenthe arm and the helix.

3. In combination with spaced coil springs, means for yieldablyconnecting the springs together including crossed helical couplingscomprising two strands of helical coiled resilient wire mediallyinterlaced, each wire having a single looped end portion extending in aplanesubstantially parallel to its longitudinal axis and terminating ina laterally extending bow-shaped arm in loop closing relation to the endof the coil, whereby to retain

